Add preliminary package structure and API (#3)

build.sbt

@@ -5,7 +5,8 @@ scalaVersion := "2.12.8"
 lazy val Benchmark = config("bench") extend Test
 lazy val bench = taskKey[Unit]("Run Benchmarks")
 
-lazy val enso = (project in file(".")).aggregate(syntax)
+lazy val enso = (project in file("."))
+  .aggregate(syntax, pkg)
 
 lazy val syntax = (project in file("syntax"))
   .configs(Benchmark)
@@ -18,9 +19,9 @@ lazy val syntax = (project in file("syntax"))
     publishArtifact := false,
     libraryDependencies ++= Seq(
       "com.storm-enroute" %% "scalameter" % "0.17" % "bench",
-      // "org.typelevel" %% "cats-core" % "1.6.0",
-      // "org.scalatest" %% "scalatest" % "3.0.5" % Test,
-      // "com.lihaoyi"   %% "pprint"    % "0.5.3"
+      "org.typelevel" %% "cats-core" % "1.6.0",
+      "org.scalatest" %% "scalatest" % "3.0.5" % Test,
+      "com.lihaoyi" %% "pprint" % "0.5.3"
     ),
     resolvers ++= Seq(
       "Sonatype OSS Snapshots" at "https://oss.sonatype.org/content/repositories/snapshots",
@@ -35,3 +36,11 @@ lazy val syntax = (project in file("syntax"))
   .settings(bench := {
     (test in Benchmark).value
   })
+
+lazy val pkg = (project in file("pkg"))
+  .settings(
+    mainClass in (Compile, run) := Some("org.enso.pkg.Main"),
+    libraryDependencies ++= Seq("circe-core", "circe-generic", "circe-yaml")
+      .map("io.circe" %% _ % "0.10.0"),
+    libraryDependencies += "commons-io" % "commons-io" % "2.6"
+  )

pkg/src/main/resources/Main.luna

@@ -0,0 +1,2 @@
+def Main:
+    None

pkg/src/main/scala/org/enso/pkg/Config.scala

@@ -0,0 +1,28 @@
+package org.enso.pkg
+
+import java.io.File
+import java.io.PrintWriter
+
+import io.circe.yaml
+import io.circe.generic.auto._
+import io.circe.syntax._
+import io.circe.yaml.syntax._
+
+import scala.io.Source
+import scala.util.Try
+
+case class Config(
+    author: String,
+    maintainer: String,
+    name: String,
+    version: String,
+    license: String) {
+  def toYaml: String = this.asJson.asYaml.spaces4
+}
+
+object Config {
+  def fromYaml(yamlString: String): Option[Config] = {
+    yaml.parser.parse(yamlString).flatMap(_.as[Config]).toOption
+  }
+
+}

pkg/src/main/scala/org/enso/pkg/Main.scala

@@ -0,0 +1,15 @@
+package org.enso.pkg
+
+import java.io.File
+
+object Main extends App {
+  override def main(args: Array[String]): Unit = {
+    Package.getOrCreate(
+      new File("/Users/marcinkostrzewa/765Luna__$%%$#Project")
+    )
+    Package.getOrCreate(
+      new File("/Users/marcinkostrzewa/proper_%%$##%#project")
+    )
+    Package.getOrCreate(new File("/Users/marcinkostrzewa/Properproject"))
+  }
+}

pkg/src/main/scala/org/enso/pkg/Package.scala

@@ -0,0 +1,116 @@
+package org.enso.pkg
+
+import java.io.File
+import java.io.PrintWriter
+
+import org.apache.commons.io.FileUtils
+
+import scala.io.Source
+import scala.util.Try
+
+object CouldNotCreateDirectory extends Exception
+
+case class Package(root: File, config: Config) {
+
+  val sourceDir = new File(root, Package.sourceDirName)
+  val configFile = new File(root, Package.configFileName)
+  val thumbFile = new File(root, Package.thumbFileName)
+
+  def save(): Unit = {
+    if (!root.exists) createDirectories()
+    if (!sourceDir.exists) createSourceDir()
+    saveConfig()
+  }
+
+  def createDirectories() {
+    val created = Try(root.mkdirs).getOrElse(false)
+    if (!created) throw CouldNotCreateDirectory
+    createSourceDir()
+  }
+
+  def rename(newName: String): Package = {
+    val newPkg = copy(config = config.copy(name = newName))
+    newPkg.save()
+    newPkg
+  }
+
+  def remove(): Unit = {
+    FileUtils.deleteDirectory(root)
+  }
+
+  def move(newRoot: File): Package = {
+    val newPkg = copyPackage(newRoot)
+    remove()
+    newPkg
+  }
+
+  def copyPackage(newRoot: File): Package = {
+    FileUtils.copyDirectory(root, newRoot)
+    copy(root = newRoot)
+  }
+
+  def createSourceDir(): Unit = {
+    if (!Try(sourceDir.mkdir).getOrElse(false)) throw CouldNotCreateDirectory
+    val lunaCodeSrc = Source.fromResource(Package.mainFileName)
+    val writer = new PrintWriter(new File(sourceDir, Package.mainFileName))
+    writer.write(lunaCodeSrc.mkString)
+    writer.close()
+    lunaCodeSrc.close()
+  }
+
+  def saveConfig(): Unit = {
+    val writer = new PrintWriter(configFile)
+    Try(writer.write(config.toYaml))
+    writer.close()
+  }
+
+  def hasThumb: Boolean = thumbFile.exists
+  def name: String = config.name
+}
+
+object Package {
+  val configFileName = "package.yaml"
+  val sourceDirName = "src"
+  val mainFileName = "Main.luna"
+  val thumbFileName = "thumb.png"
+
+  def create(root: File, config: Config): Package = {
+    val pkg = Package(root, config)
+    pkg.save()
+    pkg
+  }
+
+  def create(root: File, name: String): Package = {
+    val config = Config(
+      author = "",
+      maintainer = "",
+      name = name,
+      version = "",
+      license = ""
+    )
+    create(root, config)
+  }
+
+  def fromDirectory(root: File): Option[Package] = {
+    if (!root.exists()) return None
+    val configFile = new File(root, configFileName)
+    val source = Try(Source.fromFile(configFile))
+    val result = source.map(_.mkString).toOption.flatMap(Config.fromYaml)
+    source.foreach(_.close())
+    result.map(Package(root, _))
+  }
+
+  def getOrCreate(root: File): Package = {
+    val existing = fromDirectory(root)
+    existing.getOrElse(create(root, generateName(root)))
+  }
+
+  def generateName(file: File): String = {
+    val dirname = file.getName
+    val startingWithLetter =
+      if (!dirname(0).isLetter) "Project" ++ dirname else dirname
+    val startingWithUppercase = startingWithLetter.capitalize
+    val onlyAlphanumeric = startingWithUppercase.filter(_.isLetterOrDigit)
+    onlyAlphanumeric
+  }
+}